[gtkmm/gtkmm-3-24] Remove an obsolete file

[Kjell Ahlstedt <kjellahl src gnome org>]

commit af5103caf3e446894ee7cda8f7a7d04dc4224b6d
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Wed Sep 2 16:13:29 2020 +0200

    Remove an obsolete file
    
    * docs/reference/README: Removed
    * meson.build: Exclude some git-tracked files from generated
    tarballs. Works as intended only with a new enough dist-build-scripts.py
    file from mm-common-get.

 docs/reference/README | 6 ------
 meson.build           | 9 +++++++++
 2 files changed, 9 insertions(+), 6 deletions(-)
---
diff --git a/meson.build b/meson.build
index c31b3292..32eefb39 100644
--- a/meson.build
+++ b/meson.build
@@ -336,12 +336,21 @@ if not meson.is_subproject()
     python3.path(), dist_changelog_py,
     project_source_root,
   )
+
+  # Don't distribute these files and directories.
+  dont_distribute = [
+    'docs' / 'tutorial.moved_to_gtkmm_documentation_module',
+    'examples.moved_to_gtkmm_documentation_module',
+    'HACKING',
+    'win32_installer',
+  ]
   # Add build scripts to the distribution directory, and delete .gitignore
   # files and an empty $MESON_DIST_ROOT/build/ directory.
   meson.add_dist_script(
     python3.path(), dist_build_scripts_py,
     project_source_root,
     'untracked' / 'build_scripts',
+    dont_distribute,
   )
 endif